Inhaling non-toxic particulate matter is not an acute, but a compounding, chronic risk.
Ie. unless you take a sniff of fine fiberglass dust right from the desk, you won't experience anything beside minor irritation. What IS a serious health risk, with potential for cancer and other problems, is regularly working or living in an environment with high particulate matter content in the air. That's why miners tend to have lung problems, and that's why in factories you see workers wearing dust masks...